Gerard Houllier remains in intensive care at a Liverpool hospital today as he recovers from open-heart surgery to repair an aortic dissection.

The 54-year-old Frenchman is apparently in a "comfortable" condition having been admitted to hospital after suffering from chest pains at half-time in Saturday's 1-1 draw with Leeds.

While the 11-hour operation has been a success, the serious nature of the illness will surely cast considerable doubt on his future as Liverpool's manager.

"Gerard underwent a major operation on Saturday night having been taken for tests," confirmed the Liverpool chief executive Rick Parry. "The operation was successful and they have repaired the condition, which is good news.

"Generally the cause of such a problem is high blood pressure but he is on a ventilator to keep him as calm and as stable as possible. But we are certainly talking weeks rather than days to recuperate and recover away from the club." Tests revealed that the Frenchman had not had a heart attack, as had been feared. In fact, he had suffered an aortic dissection - a condition where the inner lining of the aorta, the main artery leaving the heart, splits and affects blood flow. The surgery is considered serious and there remains a high risk of post-operative complications.

While early assessments indicate there is little chance of Houllier being able to take up the reins again at Anfield until the new year, at the very earliest, Liverpool remain publicly confident that he will return at some stage. However, Parry believes the Frenchman may have to cut back his workload in the future.

"We are confident that he will be back because we have not been told anything that indicates to the contrary," he said. "But he's going to be conscious of the fact that he'll have to be very focused on the sort of commitments he takes on. He's the sort of guy who can't say no. After something like this, anyone would have to reflect on their lifestyle and he'll have to cut out some of the extraneous work he's always been keen to do.

"It's too early to speculate on what the future holds. There's an extraordinary weight on managers these days with pressure coming from every direction. It's hard to see that getting any easier but our concern is getting him back to full fitness. He must not rush back." The Anfield managerial role has proved something of a poisoned chalice in recent years. Sitting in the stands on Saturday was Kenny Dalglish who complained of chest pains prior to resigning the post in 1991 due to stress. His successor, the current Blackburn manager, Graeme Souness, underwent triple bypass surgery 24 hours after an FA Cup semi-final against Portsmouth a year later.

The team flew to Ukraine yesterday to prepare for tomorrow's Champions League game against Dynamo Kiev, with Phil Thompson taking charge of team affairs.

Although the former Liverpool defender is Houllier's assistant, he would not be seen as a long-term replacement should the Frenchman opt out of management. "Gerard has put together a first-class backroom team who have learnt so much from him over the years," added Parry. "Now the best tonic for him is the team succeeding. The next few games will be very much matches that the team are playing for him."